The present invention relates to a method of producing plastic tank lids for motor vehicles, and the tank lids produced by such a method, wherein the tank lid is made of tough polymeric material, with the inner side of the lid being provided with one or more projections, especially a pivot arm.
Tank lids of the type contemplated by the present invention are intended for covering the access to the fuel filler cap of vehicles, wherein the outer surface of the lid is practically disposed in the plane of the outer surface of the vehicle. The inner side of the cap is provided with one or more projections, especially with an arm that is formed on the inner side and is to be pivotably connected to the vehicle.
It is to be understood that the outer surface of the tank lid must be uniform and regular, for example truely planar or curved, since irregularities of the outer surface are esthetically displeasing and can even be recognized from a distance. However, such irregularities cannot be avoided if, for example, due to contraction processes, indentations or cavities occur after the molding.
It is therefore an object of the present invention to make indentations or cavities practically ineffective during the manufacture of tank lids of the aforementioned general type.